Russian missile company Almaz Antey has conducted its own investigation of last year’s crash of the MH17 airliner.

It contradicts the official Dutch Boards investigation which says a Russian-made warhead fired by a Buk missile system in Ukraine was responsible for the disaster that killed all 298 people on board.

The Malaysian airliner crashed on July 17 2014 in rebel-controlled eastern Ukraine and was reportedly been shot down by a surface-to-air missile.

Ukraine and Western countries contend the missile was fired by Russian troops or Russian-backed rebels.

Almaz Antey’s experiment involved blowing up a Buk warhead next to the cockpit of a retired Ilyushin 86 airliner.

Yan Novikov, the chief-executive of Almaz-Antey, said that the experiment entirely refutes the Dutch Boards conclusions regarding the type of missile and the launch area.

Mr Novikov claims the plane was brought down by an older model of Buk missile no longer used by Russia. His company also believes the missile was launched near a village called Zarochenske, south-west of the crash site. This territory is controlled by the Ukrainian military.

"The company was provided with three T-shaped strike elements, which looked like 9M38M1 [model] strike elements, which caused specialists to make their conclusion on the missile type in June," he said.

In July a full-scale experiment was conducted using a BUK 9M38M1 missile and aluminium panels.

“In the course of the experiment it became absolutely evident that if the Malaysian Boeing was downed by a BUK missile, it was done with an old BUK model which does not have double-T iron strike elements,” Novikov said.

The results of the experiment were sent to Dutch investigators, however, "according to what we know was not taken into consideration," Novikov said.

In October, a second full test was conducted using the missile and a decommissioned Ilyushin Il-86 passenger airliner.

That simulation "unequivocally proved that if the plane was brought down by a BUK system, it was done with an outdated 9M38 missile from the village of Zaroshchenskoye," he said.

"The main proof that the aircraft was shot down from the direction of Snezhnoye was [the Dutch commission’s] modeling of that process and interpretation of the damage to the fuselage. It does provide a quite visual imagery of how a missile on a head-on course could damage certain areas, yet this kind of modeling does not explain at all the real-incidence angles of striking elements [hitting the aircraft]," he added.

Almaz Antey said that the missile has a life span of 25 years and last one of this type was produced in the Soviet Union in 1986. It added that all missiles of this type were decommissioned by Russian Army in 2011. The company said that Ukraine possesses 9M38 missiles, but did not blame the Ukrainian military or the rebels in the east of the country for causing the disaster.